Barely a day goes by without a new genetic finding in the news. These stories – although aimed at the public – often include scientific terms that are widely misunderstood.

I am a sleep researcher. Together with some colleagues, we investigated this problem in the context of insomnia. We first asked participants what they understood by the ‘heritability’ of insomnia. Heritability is a key genetic term that often appears in news stories and refers to the extent to which genetic influences explain differences between people. Less than a quarter of our sample selected the correct answer from four options; almost half of them chose one of the incorrect options that stated that heritability refers to the chance that someone will pass insomnia on to their children.

This suggests that when many people read about a disorder like insomnia being moderately heritable, they misunderstand what this means. Understanding genetic information matters, not just in terms of scientific understanding, but because of how it could shape people’s treatment decisions.

Most medical organisations recommend cognitive behavioural therapy (CBT) as the first-line treatment option for chronic insomnia. However, when we asked our participants about the effectiveness of different treatment options for people reporting insomnia, their answers were swayed by whether we suggested that their insomnia was caused by genes or the environment. If we suggested that the insomnia had a genetic cause, they thought CBT was less likely to be effective and drug treatments more effective as compared with when we suggested that the insomnia had an environmental cause.

This is a stark reminder of the importance of the public communication of science. Not only to avoid misunderstandings, but because of the real-life consequences that could follow.

If we’re honest with ourselves, most of us can probably think of something we are doing, or declining to do (or supporting, or buying into) that is likely to strike people of the future as an obvious example of a moral failure. Human choices are sometimes badly at odds with human ideals and, in many cases, that seems to become clearer to everyone in the rearview mirror.

I got a fresh reminder of this while recently watching the PBS documentary series The American Revolution (2025). If you know anything about that revolution, it’s hard to miss the disconnect between its lauded ideals – including the assertion, in the Declaration of Independence, that ‘all men are created equal’ – and the slavery upheld by many of the nation’s founders.

The documentary also highlights a less-known detail about the Declaration. In a draft of the colonies’ complaints against the British crown, Thomas Jefferson, himself an ‘owner’ of people, blamed the king for the Atlantic slave trade and, incongruously, called it a ‘cruel war against human nature itself’.

What’s stuck with me in particular is the way the historian Annette Gordon-Reed then sums up Jefferson’s relationship to slavery. ‘From the beginning to the end, this institution bounded his life, even though he knew it was wrong,’ she says. ‘How could you know something is wrong and still do it? Well, that is the human question for all of us.’

For me, her remark is an invitation to reflect. Hopefully, for most of us, our current behaviours don’t include anything that will be as terrible to our descendants as enslavement is to us. But the excuses we might give for acting or not acting now are likely to seem much thinner to someone living 250 years from now. And that, I think, casts a brighter light on our choices.